Add utility to log hex buffer with size len (LOG_D) and remove unused legacy hex_dump

* logging buffer is pretty useful for debugging purposes, e.g. derived key values

common/utils/utils.c

@@ -7,34 +7,6 @@
 #include <errno.h>
 #include "utils.h"
 
-
-
-const char *hexdump(const void *data, size_t data_len, char *out, size_t out_len)
-{
-    char *p = out;
-    char *endp = out + out_len;
-    const uint8_t *q = data;
-    snprintf(p, endp - p, "[%zu]", data_len);
-    p += strlen(p);
-    for (size_t i = 0; i < data_len; ++i)
-    {
-        if (p >= endp)
-        {
-            static const char ellipses[] = "...";
-            char *s = endp - sizeof(ellipses);
-            if (s >= p)
-            {
-                strcpy(s, ellipses);
-            }
-            break;
-        }
-        snprintf(p, endp - p, " %02X", *q++);
-        p += strlen(p);
-    }
-    return out;
-}
-
-
 /****************************************************************************
  **                                                                        **
  ** Name:        hex_char_to_hex_value()                                   **

common/utils/utils.h

@@ -109,8 +109,6 @@ static inline void *malloc_or_fail(size_t size)
 #define PAGE_MASK 0xfffff000
 #define virt_to_phys(x) (x)
 
-const char *hexdump(const void *data, size_t data_len, char *out, size_t out_len);
-
 // Converts an hexadecimal ASCII coded digit into its value. **
 int hex_char_to_hex_value (char c);
 // Converts an hexadecimal ASCII coded string into its value.**

openair3/SECU/key_nas_deriver.c

@@ -57,14 +57,32 @@
 #define NR_FC_ALG_KEY_DER (0x69)
 #define NR_FC_ALG_KEY_NG_RAN_STAR_DER (0x70)
 
-// #define SECU_DEBUG 1
+static void log_hex_buffer(const char *label, const uint8_t *buf, const int len)
+{
+  char hex_str[len * 2 + 1];
+  for (int i = 0; i < len; i++) {
+    snprintf(&hex_str[i * 2], 3, "%02x", buf[i]);
+  }
+  hex_str[len * 2] = '\0';
+  LOG_D(UTIL, "%s: %s\n", label, hex_str);
+}
+
+static const char* alg_type_to_str(algorithm_type_dist_t alg_type)
+{
+  switch (alg_type) {
+    case NAS_ENC_ALG: return "NAS_ENC_ALG";
+    case NAS_INT_ALG: return "NAS_INT_ALG";
+    case RRC_ENC_ALG: return "RRC_ENC_ALG";
+    case RRC_INT_ALG: return "RRC_INT_ALG";
+    case UP_ENC_ALG:  return "UP_ENC_ALG";
+    case UP_INT_ALG:  return "UP_INT_ALG";
+    default:          return "UNKNOWN_ALG_TYPE";
+  }
+}
 
 static void derive_key_common(algorithm_type_dist_t alg_type, uint8_t alg_id, const uint8_t kasme[32], uint8_t FC, uint8_t out[32])
 {
   uint8_t s[7];
-#if defined(SECU_DEBUG)
-  int i;
-#endif
 
   /* FC */
   s[0] = FC;
@@ -83,18 +101,11 @@ static void derive_key_common(algorithm_type_dist_t alg_type, uint8_t alg_id, co
   s[5] = 0x00;
   s[6] = 0x01;
 
-#if defined(SECU_DEBUG)
-  printf("%s FC %d nas_alg_type distinguisher %d nas_enc_alg_identity %d\n", __FUNCTION__, FC_ALG_KEY_DER, alg_type, alg_id);
-
-  for (i = 0; i < 7; i ++) {
-    printf("0x%02x ", s[i]);
-  }
-
-  printf("\n");
-#endif
-
   byte_array_t data = {.len = 7, .buf = s};
   kdf(kasme, data, 32, out);
+  log_hex_buffer("Input key (kgnb)", kasme, 32);
+  log_hex_buffer("Derivation string (s)", s, 7);
+  log_hex_buffer(alg_type_to_str(alg_type), out, 32);
 }
 
 /*!
@@ -165,10 +176,9 @@ void derive_kgnb(uint8_t kamf[32], uint32_t count, uint8_t *kgnb)
   byte_array_t data = {.buf = input, .len = 10};
   kdf(kamf, data, 32, kgnb);
 
-  printf("kgnb : ");
-  for (int pp = 0; pp < 32; pp++)
-    printf("%02x ", kgnb[pp]);
-  printf("\n");
+  log_hex_buffer("KAMF", kamf, 32);
+  log_hex_buffer("KDF input for kgnb", input, 10);
+  log_hex_buffer("Derived kgnb", kgnb, 32);
 }
 
 void derive_keNB(const uint8_t kasme[32], const uint32_t nas_count, uint8_t *keNB)
@@ -260,6 +270,9 @@ void nr_derive_key_ng_ran_star(uint16_t pci, uint64_t nr_arfcn_dl, const uint8_t
   byte_array_t data = {.buf = s, .len = 10};
   const uint32_t len_key = 32;
   kdf(key, data, len_key, key_ng_ran_star);
+  log_hex_buffer("Input key", key, 32);
+  log_hex_buffer("KDF input for ng_ran*", s, 10);
+  log_hex_buffer("Derived key_ng_ran*", key_ng_ran_star, 32);
 }
 
 void derive_skgNB(const uint8_t *keNB, const uint16_t sk_counter, uint8_t *skgNB)

openair3/SECU/key_nas_deriver.h

@@ -5,6 +5,8 @@
 #include <stdlib.h>
 #include <stdint.h>
 
+#define SECURITY_KEY_LEN 32
+
 typedef enum {
   NAS_ENC_ALG = 0x01,
   NAS_INT_ALG = 0x02,